The rate constant for the radioactive disintegration of Co is 0.1317 ycai’. Calculate the mass of Co that will remain after 21.04 years out of I gram sample.

Based on Beer-Lambert law, explain the method of finding out the concentration of a given solution of potassium dichromate. You are also provided with a standard solution of potassium dichromate.

Calculate the ratio for the fundamental frequencies of HI and DI.

What is the essential condition for a molecule to be microwave active? Give three examples each for the diatomic molecules. 

i) having microwave activity and

ii) not having microwave activity.

The bond length of HI molecule is 163 pm. Calculate its(i) moment of inertia and (ii) rotational constant.

Explain the terms, racemic mixture and meso form, with an example in each case. Mention a difference between the two

(Fe(CN)6) 3- is a low-spin complex ion while (Fe(H2O)6) 3+ is a high-spin complex ion. Both the complex ions are derived from ferric (Fe(III)) ion. Following the example worked out for d 4 configuration in Sec. 6.8 of Unit 6, answer the following:

i) What is the number of electron in 3d level of Fe3+ ion?

ii) Indicate the number of unpaired electrons in 3d level of Fe (III) species in each of the complex ions. Predict the magnetic moments of both the complex ions in Bohr magnetion units

You are given a gaseous substance. Suggest an experimental method to find out whether it is polar or nonpolar. Discuss the steps to be used in this method.

An element X forms a compound, XOCl3, in which X and O form a double bond while X and Cl form single bonds. Identify X from the following elements:

i) Al

ii) Si

iii) P

(iv) S.

Give reason for your answer. Predict the shape of the molecule.

Hint: Start from molecular orbital configuration for oxygen molecule and peroxide Ion; then calculate bond order for each

Using the molecular orbital theory, explain why the oxygen-to-oxygen bond is stronger in oxygen molecule than in peroxide O( ) 2 2 ion

State the definitions of bonding, antibonding and nonbonding orbitals. Draw the molecular orbitals obtained by the linear combination of two 1s orbitals

Starting from Lewis structures, determine the hybridisation type of the central atoms in  4 IF and ICI  4 .

Explain the structure of BF3 molecule based on hybridization concept. What is its shape

Calculate the bond lengths in bromoethane and bromoethylene using covalent radii values given in Table 3.10 of Unit 3. For hydrogen, assume that the covalent radius in 28 pm in these compounds.

Arrive at the Lewis structures of 2 ICI and  2 ICI ions. Using VSEPR theory, predict the shapes of these compounds.

Calculate the de Broglie wavelength associated with a body of mass 1.5 kg moving with a velocity of 100 m s

Write the values of four quantum numbers for 4s and 4p electrons

Calculate he wave number (m-1) and energy (kJ mol)-1 of the light of wavelength 800 nm.

Calculate the radius of the second and third orbits in He+ ion. Also calculate the energy of the electron in the second and third orbits of He+ ion.  Hint: Use Bohr atom model. Z value for He+ ion = 2.